The president of Guatemala is under pressure to investigate an attack by an armed gang on the editor of the independent newspaper El Periodico.

Jose Ruben Zamora and his family complain of being held hostage by for three hours earlier this week.

Mr Zamora says his children were beaten while he was stripped, blindfolded and forced to kneel at gunpoint.

During the ordeal, Mr Zamora quotes one of his attackers saying: "If you value your children stop bothering the people above.

"I don't know who you've annoyed high up the ladder, but we have orders that someone up high despises you.

"Whatever you do, do not report this."

The World Association of Newspapers (WAN) has called on President Alfonso Portillo to ensure the state provides an environment in which journalists are able to carry out their professional duties without fear of attack and intimidation.

WAN says such incidents foster a climate of fear that inhibits journalistic investigation and can promote self-censorship.

It asks Mr Portillo to ensure the attack is "fully and impartially investigated and that those responsible are swiftly brought to justice".

Jose Ruben Zamora is now back at his desk.

"I have no other choice but to continue working to inform the Guatemalan people of what is going on," he said.

The WAN letter to President Portillo was also copied to the permanent representative to the United Nations in Guatemala City.

'Atmosphere of intimidation'

It is the second time this year that WAN has intervened on Mr Zamora's behalf.

Late last year El Periodico carried an article claiming that the Portillo government was benefiting financially as a direct result of the acceptance of funds from mafia activities, including trafficking in narcotics, kidnapping and extortion.

We are all vulnerable to delinquency in this country and I have a duty to carry on

Jose Ruben Zamora

The report was the culmination of eight years of research and drew lines between the leaders of organised crime and some government and military heads.

Soon after the publication of the article a team of government auditors camped out in El Periodico's offices to carry out an audit. They stayed for 40 days.

Shortly after the WAN intervention they left. No charges followed that investigation.

According to Mr Zamora, several staff at the paper have since received threatening phone calls and he says that, as a result, there is an atmosphere of intimidation hanging over the newsroom.

Mr Zamora is determined to lead from the front to ensure the continuation of a strong independent media in his country.

"Yes, I fear for the safety of my family and I have personally suffered aggression in the past, but we are all vulnerable to delinquency in this country and I have a duty to carry on," he said.

The US Ambassador to Guatemala, John R Hamilton, visited Mr Zamora on the day of the attack, which he described as "violent and barbaric".

He said the crime was a blow to all journalists "and to the good name of Guatemala".

"Those who would crush freedom of speech will find that there are many brave voices, in addition to Zamora's, who will continue to report in the newspapers, on radio and on television," the ambassador said.